Alteration of Proteoglycan Metabolism during the differentiation of 3T3-L1 fibroblasts into Adipocytes
Author
Summary, in English
3T3-L1 fibroblasts were induced to differentiate to 3T3-L1 adipocytes by dexamethasone, isobutyl-methylxanthine, and insulin. To study how differentiation affects extracellular matrix production, the accumulation of proteoglycans was studied by labeling the 3T3-L1 cells with [35S]sulphate for 24 h. The labeled proteoglycans were isolated from the medium and cell layer extracts by anion-exchange chromatography. They were then taken to gel filtration chromatography on Superose 6 before or after chondroitin ABC lyase digestion. Hyaluronan was determined by radioimmunoassay. The rate of accumulation of proteoglycans and hyaluronan in the control 3T3-L1 fibroblasts increased with time whereas it decreased slightly in the age matched adipocytes where the differentiation had proceeded, as judged by the change of morphology and increase of the activity of the adipose conversion markers glycerol-3-phosphate dehydrogenase and hormone sensitive lipase. The main change noted was that the adipocytes accumulated 50-70% less amount of small proteoglycans (decorin) in the medium than the fibroblasts did. The amount of large chondroitin/dermatan sulphate proteoglycans was also decreased but to a considerably smaller extent (30%). In the cell layer, heparan sulphate proteoglycan decreased by 60% as compared with the control cells. Thus, the differentiation of 3T3-L1 fibroblasts into adipocytes, which changes the morphology and the function of the cells, is also accompanied by a decreased net production especially of proteoglycans typical of fibrous connective tissue.
Department/s
- Mathematics (Faculty of Sciences)
- Matrix Biology
- Infection Medicine (BMC)
Publishing year
1991
Language
English
Pages
821-826
Publication/Series
Journal of Cell Biology
Volume
114
Issue
4
Document type
Journal article
Publisher
Rockefeller University Press
Topic
- Mathematics
Keywords
- 3T3-L1 adipocytes
- matrix proteins
- decorin
- differentiation
Status
Published
Research group
- Matrix Biology
ISBN/ISSN/Other
- ISSN: 0021-9525